This invention relates to locks and more particularly to a lock which does not require a key for opening it. It is further directed to a lock which eliminates the requirement for visual contact with the lock to effect disengagement thereof.
In the past there have been several types of keyless locks which have been constructed to operate by rotable wheels having certain numerical permutations which when properly set disengage the lock. However, such locks have generally required the operator to have visual contact with the lock so that the operator can see the numbers on the wheels which would indicate the settings of the tumblers in order to set the combination to open the lock.
One such example is illustrated in U.S. Pat. No. 86,908 entitled "Permutation Lock". This early patent illustrates the use of a series of three wheels each of which has a flat depression located along the periphery of the wheel. The operator rotates each of the three wheels to the proper position according to a preset combination, and three respective bolts are permitted to fall flat onto the flat portions of the wheel thereby releasing the slide bolt locking mechanism. This then releases the lock. However, this device requires the operator to see the numbers on the wheels so that the operator must have visual contact with the wheels in order to set the proper combination.
Another device is illustrated in U.S. Pat. No. 543,404 entitled "Lock". In this device there are a series of wheels which have a gear tooth mounted thereon, with a pawl holding the gear tooth in position. The operator depresses each of a series of external levers to operate the pawl to rotate the gear tooth and the wheels. Each of the wheels includes a recess so that when all of the wheels are in the proper position, a lock arm is permitted to fall downwardly into the recesses. The lock arm thereby releases the bolt which may then be slid laterally to open the lock. This device does not have a zeroing or reference position to set the wheels such that the operator can operate each external lever a predetermined number of times from the reference position in order to effectuate opening of the lock. This device uses a friction brake which must be sensed by the operator to establish reference position. Thus, the operators sense of feeling the reference position by means of the friction brake introduces the possibility for error which is dependent upon the sense of touch of the operator.
U.S. Pat. No. 1,123,061 entitled "Padlock" illustrates a series of four levers having external knobs positioned thereon. Only one of the knobs will operate to release the latch and thereby permit the lock to open. The elongated lever which will operate the lock causes a pivoting of the latching bolt thereby releasing the shackle. This lock does not require a numerical permutation in order to release the lock.
U.S. Pat. No. 1,056,667 shows a keyless lock wherein there are a series of four wheels which have numerical designations thereon. As the knobs are turned, the inner ends of the knobs are constructed in the form of pins having recesses in order to permit the stops on a bolt operating member to slide into the recesses. When the pins on the knobs are turned in the right direction, according to a predetermined combination, each of the stops will be permitted to slide into an appropriate recess, such that the bolt will be permitted to slide thereby releasing the latch. Again, this device requires the operator to visually see the knobs and dial the proper combination to open the lock.
The "Permutation Lock" illustrated in U.S. Pat. No. 1,483,993 illustrates a locking device which can lock a bolt in either of two positions. A notch is positioned on the tumbler to either align with the bolt permitting the bolt to slide or to not align with the bolt, prohibiting movement. The position of the tumbler is changed by a push button and pawl arrangement. A brake is applied to the tumbler to keep it from movement until the brake is released.
The main problem with the patents illustrated in the prior art is that they cannot easily and conveniently be used by a person who cannot see or have visual contact with the lock. Particularly, the operator must be able to see the numbers on the lock operator so that the proper combination can be dialed and set. The present invention uses a lock which eliminates this requirement. Particularly, the operator must only push the push-button operators to increment internal ratchet wheels to the proper position such that the shackle can be released from the lock. The operator can further initiate an operation which will set the ratchet wheels to a predetermined initial reference orientation. From this reference position, the operator can operate each push-button the predetermined number of times, which is the preset combination of the lock, such that the ratchet wheels will be in the proper lock opening position. All of this can be done without the operator seeing the lock or the push-button operators.
The inventive lock is permitted to be opened when the ratchets are in the proper lock opening position by merely pulling on the lock casing or shackle. This causes a locking bar to exert a force on internal members of the lock, which cause pins to be forced into and received by aligned slots on the ratchet wheel, which permits the locking bar to be moved into a lock opening condition. When the slots on the ratchet wheel are not in proper alignment, the locking bar cannot be moved nor the shackle released from the lock casing.
Thus, it is an object of the present invention to provide a keyless lock which eliminates the requirement for visual contact with the lock by the operator to effect disengagement thereof. Related thereto is the object of providing a keyless lock which has push-button operators as a part of the lock, the push-button operators being operable to rotate internal ratchet wheels of the lock such that the ratchet wheels can be aligned in a proper lock opening position by merely pushing the push buttons a proper number of times according to a predetermined numerical code. It is a related object to provide a keyless lock as described above wherein the ratchet wheels are set to a predetermined reference position by the operator before initiating the numeric code in push-button sequence.
Many other objects and advantages of the invention will be clear from the following detailed description of the preferred embodiment.